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ICE agent opened fire on supervisor at office, sources say

A shooting that left one federal immigration agent dead and another wounded appears to have been a dispute between an agent and his supervisor, law enforcement sources told the Los Angeles Times.

The gunman opened fire on the male supervisor shortly before 6 p.m. in the building, according to the sources, who asked not to be named because they were not authorized to speak on the matter.

With the supervisor wounded, a third agent intervened and opened fire on the gunman, who was pronounced dead at the scene, according to law enforcement authorities. The male agent who killed the gunman was uninjured.

The supervisor was taken by a Long Beach Fire Department ambulance to nearby St. Mary Medical Center, where he was being treated late Thursday. He was in stable condition.

The FBI agents were interviewing witnesses and processing the crime scene at the Glenn M. Anderson Federal Building.

"At this time we believe this was an isolated incident and that the shooter acted alone," Steven Martinez, assistant director in charge of the Los Angeles FBI office, told reporters at the scene.

Claude Arnold, special agent in charge of the ICE office in Los Angeles, declined to provide details on the shooting because of the ongoing investigation. He also said that the names of the agents were not being released because relatives had not been notified.

"Obviously, there's still many questions that remain to be answered," Arnold said. "Our hearts go out to all those who have been affected."

The Long Beach Police Department, which initially responded to the call, was investigating the shooting with the FBI. They were being aided by the ICE office of Professional Responsibility.